Many clinical diagnostics and biotechnology processes utilize complex, conditions-sensitive processes. One such process is temperature-sensitive enzymatic amplification of nucleic acids. Such a polymerase chain reaction (PCR) is routinely used to produce multiple copies of sequence-specific nucleic acid molecules in order to facilitate their detection, sequencing, or cloning. For example, viral and bacteria pathogens can be detected in blood and saliva samples by amplifying nucleic acid sequences specific to those pathogens and assaying any amplification product using fluorescence detection. For a wide range of clinical and non-clinical applications, PCR-based assays are considered superior assays.
Compared to immunoassays, however, PCR-based processes are considered tedious, time consuming, prone to contamination, and labor intensive. In PCR-based assays, nucleic acids typically extracted and isolated from cell culture or clinical specimens such as blood, urine or saliva, so that the isolated nucleic acids are in sufficiently pure form to serve as a suitable template for amplification. Moreover, the reagents for the amplification step are labile and must be stored at low temperatures. Just prior to performing the PCR, the reagents are thawed and introduced into the PCR reaction vessel or chamber in precise amounts, along with the nucleic acid template isolated from the sample. Other sensitive assays are also time-consuming and require careful monitoring by trained personnel.
Accordingly, there are numerous assays and techniques in the art that require careful attention to using precise quantities of reagents. Accordingly, there is a need in the art for methods and devices capable of storing metered quantities of reagents for an extended period of time and in a manner that renders the reagents accessible during a chemical reaction with minimum intervention from a user.